Sliding Filament Theory Px

Front

What is the Sliding Filament Theory?

Back

The Sliding Filament Theory explains how muscles contract by the sliding of actin filaments over myosin filaments, resulting in the shortening of the sarcomere.

Front

What role does ATP play in muscle contraction?

Back

ATP binds to myosin heads, causing them to release from actin and allowing the muscle contraction cycle to continue.

Front

What are troponin and tropomyosin?

Back

Troponin and tropomyosin are proteins that cover the myosin binding sites on actin, preventing muscle contraction when calcium levels are low.

Front

What triggers the release of calcium from the sarcoplasmic reticulum?

Back

An action potential triggers the release of calcium from the sarcoplasmic reticulum, initiating muscle contraction.

Front

What happens during the power stroke in muscle contraction?

Back

During the power stroke, myosin heads pull actin filaments inward, causing the sarcomere to shorten.

Front

What is the role of calcium in muscle contraction?

Back

Calcium binds to troponin, causing a conformational change that moves tropomyosin away from the myosin binding sites on actin.

Front

What occurs immediately after ATP hydrolysis?

Back

After ATP hydrolysis, myosin heads bind further along the actin filament, continuing the contraction cycle.

Front

What is the resting state of a sarcomere?

Back

The resting state of a sarcomere is when the actin and myosin filaments are not interacting, and the muscle is relaxed.

Front

What is the function of the sarcoplasmic reticulum?

Back

The sarcoplasmic reticulum stores calcium ions and releases them during muscle contraction.

Front

What happens to actin during muscle contraction?

Back

Actin slides inward towards the center of the sarcomere during muscle contraction.